Screen decks typically are utilized to screen materials such as coal, sand, gravel, limestone, crushed stone, ores or the like. Existing screen decks include a screening surface having a plurality of apertures therethrough of a size selected for the particular material being screened.
The material typically is provided in bulk onto a top surface of the screen deck where smaller particles of the material filter through the apertures and are collected beneath the screen. Larger particles of material greater than the size of the apertures remain above the top surface and either run off or are removed from the screen for further processing.
The screen deck must be formed from a material strong enough to support the weight of the material being screened without deformation. Additionally, since the material to be screened frequently includes water and/or chemicals, the material forming the screen deck must be substantially impervious to rust and corrosion.
To provide the desired strength and corrosion resistance, screen decks typically are formed from metal and are coated with another material, such as plastic or the like. Screen decks can be provided as a unitary surface or as modular systems with a plurality of interchangeable panels.
In order to provide a constant flow of material to be screened through the screen apertures and to provide a flow of large particles of material across the screen deck, the screen deck is typically positioned at a predetermined slope or incline. The large particles of material can then flow across the top surface of the screen deck for collection and further processing while the smaller particles of material fall through the apertures and are collected beneath the screen deck.
In some applications, the flow of material to be screened flows too fast across the surface of the screen deck which inhibits filtering of the smaller particles of material therethrough. To regulate the flow of material across the surface of the screen deck, dam members are positioned across the surface of the screen deck.
Existing dam members, however, are permanently secured to the unitary deck surface or individual deck panels in a modular system. Accordingly, in order to modify the deck surface to include, remove or substitute a dam member, the entire deck surface or affected panels must be removed and replaced with a different deck surface or panels as desired. Such modification is expensive, not only due to the labor involved in the modification but also in stocking a variety of unitary deck surfaces or deck panels having attached dam members of different sizes and configurations.
It therefore would be desirable to provide a dam member for use with a screen deck which is releasably secured to a portion of the screen deck and readily can be removed and replaced as desired.